Material property testing system and method

ABSTRACT

Systems, methods, devices, and circuitries are provided for determining a material property. In one embodiment, a method includes applying non-thermal energy to a first side of a material sample; sensing, a response of the material sample to the non-thermal energy; generating non-thermal data indicative of the response; and determining a thermal property of the material sample based on the non-thermal data.

This application claims priority to U.S. Application No. 17/289,348,filed on Apr. 28, 2021, which is a National Phase entry application ofInternational Patent Application No. PCT/US2019/059074 filed on Oct. 31,2019, which also claims priority to U.S. Provisional Pat. ApplicationNo. 62/754,671 filed on Nov. 2, 2018, entitled “SYSTEM AND METHOD FOREVALUATING THERMAL INSULATION FOR FABRIC,” also claims priority to U.S.Provisional Pat. Application No. 62/861,341 filed on Jun. 14, 2019,entitled “MATERIAL PROPERTY TESTING SYSTEM AND METHOD,”, the contents ofwhich are herein incorporated by reference in their entirety.

STATEMENT UNDER 35 U.S.C. 202(C)(6)

This invention was made with Government support under Grant Number19134080 awarded by the National Science Foundation. The Government hascertain rights to this invention.

BACKGROUND

Many materials are selected for specific applications based on theirthermal properties, such as thermal resistance an thermal conductance.The thermal resistance of a material characterizes or quantifies thelevel of thermal insulation provided by the material. The thermalresistance of a material may be expressed in several ways, including“R-value,” thermal insulance, or intrinsic thermal insulation (measuredin m²K/W); absolute thermal resistance (measured in K/W), or specificthermal resistance (measured in mK/W). The thermal resistance of amaterial is an important characteristic when the material will be usedin buildings or other structures, apparel, household goods, electronicdevices, and so on.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1E illustrate an exemplary material property measurement devicein accordance with various aspects described.

FIGS. 2 and 2A illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 3, 3A-3B illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 4, 4A-4C illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 5, 5A-5D illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 6A-6D illustrate an exemplary material property measurement devicein accordance with various aspects described.

FIGS. 7, 7A-7D illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 8 and 8A illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIGS. 9 and 9A illustrate an exemplary material property measurementdevice in accordance with various aspects described.

FIG. 10 illustrates how material property measurement techniques may beused to identify a material type identifier in accordance with variousaspects described.

FIG. 11 illustrates an exemplary material property measurement method inaccordance with various aspects described.

FIG. 12 illustrates an exemplary material property evaluation method inaccordance with various aspects described.

FIG. 13 illustrates an exemplary material property measurement method inaccordance with various aspects described.

FIG. 14 illustrates an exemplary material property measurement method inaccordance with various aspects described.

FIG. 15A illustrates an exemplary material property measurement devicein accordance with various aspects described.

FIG. 15B illustrates an exemplary material property measurement methodin accordance with various aspects described.

FIGS. 16 and 17 illustrate exemplary displays/user interfaces for ameasurement device in accordance with various aspects described.

DESCRIPTION

The determination of a material’s thermal resistance is typically madein a laboratory environment using expensive and cumbersome testequipment and lengthy test procedures. However, in some circumstances aconsumer or other non-technical person may want to determine orapproximate a material’s thermal resistance. For example, a personchoosing a building material for a home project may be interested indetermining the comparative thermal resistance of two different types ofwall coverings. A person choosing camping gear may want to know thethermal resistance of a sleeping bag or coat they are consideringpurchasing. A parent choosing a garment for their baby may want to knowthe thermal resistance of different garments to maximize the baby’scomfort. A person exercising or competing in a sport may want to knowwhether a garment is suitable for the environmental conditions. Thereare other properties of materials that may be of interest to usersmaking a material selection such as the present moisture content of thematerial and/or the compressibility or softness of the material. In thefollowing description, the term “baby” will be used as a shorthandnotation to refer to the person who is wearing a garment made of thematerial under test.

Disclosed herein are measurement systems and methods that facilitate themeasurement of various material properties using a measurement devicethat is suitable for use by a consumer. The measurement device may behandheld or portable and affordable for purchase for household use.

In some instances simply knowing a garment’s various properties, such asthermal resistance, is not sufficient to enable a consumer to select asuitable material for a given purpose or application. Thus, assessingthe suitability of the material’s properties for a given environment orapplication is another potentially useful feature provided by someexamples of the measurement device described herein. It may also behelpful for the measurement device to evaluate and report selectedcharacteristics of the present environment (e.g., temperature, humidity,air quality) that may aid a consumer in selecting a material for use inthe environment.

Portions of the following description will be in the context of ameasurement device that determines one or more properties, such asthermal resistance, of a garment’s fabric. One possible application ofthe described measurement device and method is to determine thesuitability of a given garment for a given environment (e.g.,temperature and/or humidity). The measurement device can be used byindividuals seeking a garment that will be suitable (e.g., comfortable)for their environment (or predicted environment). The measurement devicecan be used by caregivers to select garments for babies or adults undertheir care that may not be able to provide feedback on their comfort.While many specific examples are presented, it is to be understood thatthe described methods, devices, and circuitries are also applicable tothe thermal property measurement of any material.

The disclosed measurement device utilize non-thermal energy sources andsensing technologies to determine a thermal property of a material orgarment, thereby facilitating fast, simple evaluation of the thermalproperty by a consumer. For the purposes of this description, the term“thermal property” is to be broadly construed as including any propertythat affects a level of comfort in terms of the wearer’s bodytemperature. Examples of thermal properties include breathability,thickness, thermal resistance, thermal conductivity, compressibility,and so on.

The present disclosure will now be described with reference to theattached figures, wherein like reference numerals are used to refer tolike elements throughout, and wherein the illustrated structures anddevices are not necessarily drawn to scale. As utilized herein, terms“module”, “component,” “system,” “circuit,” “element,” “slice,”“circuitry,” and the like are intended to refer to a set of one or moreelectronic components, a computer-related entity, hardware, software(e.g., in execution), and/or firmware. For example, circuitry or asimilar term can be a processor, a process running on a processor, acontroller, an object, an executable program, a storage device, and/or acomputer with a processing device. By way of illustration, anapplication running on a server and the server can also be circuitry.One or more circuits can reside within the same circuitry, and circuitrycan be localized on one computer and/or distributed between two or morecomputers. A set of elements or a set of other circuits can be describedherein, in which the term “set” can be interpreted as “one or more.”

As another example, circuitry or similar term can be an apparatus withspecific functionality provided by mechanical parts operated by electricor electronic circuitry, in which the electric or electronic circuitrycan be operated by a software application or a firmware applicationexecuted by one or more processors. The one or more processors can beinternal or external to the apparatus and can execute at least a part ofthe software or firmware application. As yet another example, circuitrycan be an apparatus that provides specific functionality throughelectronic components without mechanical parts; the electroniccomponents can include one or more processors therein to executeexecutable instructions stored in computer readable storage mediumand/or firmware that confer(s), at least in part, the functionality ofthe electronic components.

It will be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be physicallyconnected or coupled to the other element such that current and/orelectromagnetic radiation (e.g., a signal) can flow along a conductivepath formed by the elements. Intervening conductive, inductive, orcapacitive elements may be present between the element and the otherelement when the elements are described as being coupled or connected toone another. Further, when coupled or connected to one another, oneelement may be capable of inducing a voltage or current flow orpropagation of an electro-magnetic wave in the other element withoutphysical contact or intervening components. Further, when a voltage,current, or signal is referred to as being “applied” to an element, thevoltage, current, or signal may be conducted to the element by way of aphysical connection or by way of capacitive, electro-magnetic, orinductive coupling that does not involve a physical connection.

As used herein, a signal that is “indicative of” a value or“corresponding to” other information may be a digital or analog signalthat encodes or otherwise communicates the value or other information ina manner that can be decoded by and/or cause a responsive action in acomponent receiving the signal. The signal may be stored or buffered incomputer readable storage medium prior to its receipt by the receivingcomponent and the receiving component may retrieve the signal from thestorage medium. Further, a “value” that is “indicative of” somequantity, state, or parameter may be physically embodied as a digitalsignal, an analog signal, or stored bits that encode or otherwisecommunicate the value.

As used herein, “determine” or “determining” some quantity orcharacteristic is to be construed in non-limiting manner to includedirectly or indirectly measuring, estimating, calculating, reading datafrom storage medium, approximating, receiving data from anothercomponent, identifying, receiving a signal from a measurement device,computing, and so on. The function of determining may be performed bycircuitry or hardware components and/or computer-executable instructionsin execution by a processor or device.

As used herein, a signal may be transmitted or conducted through asignal chain in which the signal is processed to change characteristicssuch as phase, amplitude, frequency, and so on. The signal may bereferred to as the same signal even as such characteristics are adapted.In general, so long as a signal continues to encode the sameinformation, the signal may be considered as the same signal. Forexample, a transmit signal may be considered as referring to thetransmit signal in baseband, intermediate, and radio frequencies.

Use of the word example is intended to present concepts in a concretefashion. The terminology used herein is for the purpose of describingparticular examples only and is not intended to be limiting of examples.As used herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises,”“comprising,” “includes” and/or “including,” when used herein, specifythe presence of stated features, integers, steps, operations, elementsand/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components and/or groups thereof.

In the following description, a plurality of details is set forth toprovide a more thorough explanation of the embodiments of the presentdisclosure. However, it will be apparent to one skilled in the art thatembodiments of the present disclosure may be practiced without thesespecific details. In other instances, well-known structures and devicesare shown in block diagram form rather than in detail in order to avoidobscuring embodiments of the present disclosure. In addition, featuresof the different embodiments described hereinafter may be combined witheach other, unless specifically noted otherwise.

FIGS. 1A-1E illustrates various aspects of an exemplary thermal propertymeasurement device 100 configured to be portable, handheld, and suitablefor consumer use. In FIG. 1A, general components of the device 100 canbe seen, including a portable housing that includes a first member 110,a second member 120, a clamping mechanism 130 connecting the firstmember to the second member, and a handle mechanism 140 that is operableto move the first member and the second member between an open positionand a closed position.

In the open position (not shown), the first member and the second memberare positioned relatively widely apart from one another. The clampingmechanism includes a pivot point about which handle members can be movedto open and close the first and second members. As illustrated best inFIG. 1E in the closed position an inside surface of the first member 110contacts a first side of a material sample and an inside surface of thesecond member 120 contacts a second side of the material sample oppositethe first side. In one example, the clamping mechanism 130 is configuredto maintain an orientation of the first member normal or perpendicularto the second member as the device is moved between the open positionand the closed position. In this example the clamping mechanism mayinclude a linkage arrangement rather than or in addition to a pivotarrangement.

In one example, the clamping mechanism 130 includes a feature thatlimits a pressure applied to the material sample when the first memberand the second member are in the closed position. For example, theclamping mechanism may include a spring that relieves the clampingpressure beyond some limit. As will describe in more detail in FIG. 6C,the clamping mechanism may be a servo motor configured to move themembers together until contact with the material is sensed. A separaterelief feature may be included that prevents the device 100 from overlycompressing a sample material being measured which may degrade themeasurement quality.

Indicia circuitry 150 disposed in the housing 140 is configured tocommunicate information related to a determined material property. Theindicia circuitry 150 may be configured to display indicia indicative ofthe information and/or generate an audible signal indicative of theinformation. In one example indicia circuitry 150 causes a mobilecommunication device (e.g., cellphone) to display the information. Inthis example, the indicia circuitry 150 includes storage medium storingcomputer-executable instructions that, when executed by a mobilecommunication device 155, cause the mobile communication device toreceive the information and display the information on the mobilecommunication device as illustrated in FIG. 1B. These instructions aretransmitted to a mobile device during set up.

FIG. 1C illustrates a functional block diagram of electronic aspects ofthe thermal property measurement device 100. Many of these electronicaspects are not explicitly labeled in other figures for the sake ofsimplicity. The device 100 includes a measurement system 160 thatincludes a source element 163 in the first member 110 and at least onesensor element 165. The device 100 also includes measurement circuitry170 configured to control the source element 163 to apply energy to thesample material and the sensor element 165 to generate data indicativeof the sample material’s response to the energy. The measurementcircuitry 170 and/or analysis circuitry 180 may be embodied as aprocessor executing instructions for performing the described functionsof the measurement circuitry 170 and/or analysis circuitry 180.

An environmental sensor 105 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 100. The analysis circuitry 180 is configured todetermine a thermal property of the sample material based on the datafrom the measurement circuitry and provide information related to thethermal property to the indicia circuitry 150. In one example, theanalysis circuitry 180 receives environmental characteristic data fromthe environmental sensor element 105 and determines, based on thethermal property, if the material is suitable for the environment. Inone example, the analysis circuitry 180 is configured to combinedetermined thermal properties for multiple layers (e.g., adding thethermal resistance of a garment and a sleep sack) and provideinformation related to the combined thermal properties to the indiciacircuitry. In one example, the environmental characteristic data isreceived from an external source by way of interface circuitry 141. Forexample, weather forecast data from a mobile device may be wirelesslytransmitted (e.g., Bluetooth) to the analysis circuitry. The determinedsuitability may be displayed on the indicia circuitry 150. Recall thatthe indicia circuitry 150 may be integrated with the device as shown inFIG. 1A or at least partially integrated with a mobile communicationdevice 155 as shown in FIG. 1B.

In one example, a base station or docking station 101 is provided intowhich the measurement device 100 may be docked (e.g., by way of wiredinterface 141) to allow for wired communication between the measurementdevice 100 and another device and/or to charge the measurement device.In this example, the base station communicates with the measurementdevice in a same manner as a cellphone may communicate wirelessly withthe measurement device. Alternatively, a cellphone or other device maybe plugged into the base station to enable communication between thecellphone or other device and the measurement device 100 when a wirelessconnection is not available.

In one example, the analysis circuitry 180 is configured to leverage theprocessing power of an external device (e.g., a cellphone’s imageprocessing capabilities). In this example, the analysis circuitryincludes storage medium storing computer-executable instructions that,when executed by the mobile communication device 155 of FIG. 1B, causethe external device to receive data, process the data, and transmit thedata back to the analysis circuitry 180 for use in determining thethermal property. These instructions may be transmitted to the externaldevice during setup.

The measurement device 100 may include storage medium 135 that isconfigured to store data used by the device in determining theinformation that is displayed by indicia circuitry 150. If the storagemedium 135 is not internal to the measurement device 100, the storagemedium is accessible to the device by way of a communication link to anexternal storage medium. Examples of types of data that may be stored instorage medium 135 (e.g., in the form of lookup tables, databases, andso on) include data mapping non-thermal response (indicative of amaterial’s response to a non-thermal stimulus) to thermal propertyvalues and data mapping thermal property values to ranges ofenvironmental characteristics (e.g., thermal resistance values mapped toranges of temperatures in which material having the thermal resistancewill be comfortable). Data encoding external device instructions (thatmay be transmitted to a user’s device during setup to enablecommunication and/or co-processing of data) may be stored. Environmentalacceptability criteria (e.g., acceptable temperature/humidity rangesrepresenting a default set of ranges or a custom set of ranges asdetermined for a particular user) may be stored.

User specific biometric data may also be stored (e.g. age, gestationalage, weight, sex) for use in determining suitable calibration schemesand/or processing algorithms to use when determining recommendations, orto adjust calibration constants ensuring the device operation istailored to the given application / user. For example, for premature orunderweight babies (as determined by the user specific data) the thermalresistance recommended by the device for a given ambient temperature maybe slightly increased. Usage data which is collected during use of thedevice may be stored for use in providing historical feedback and/oradapting the operation of the device to fit a particular user’scharacteristics.

Data mapping non-thermal response to material type may also be storedfor use in identifying a material type in addition to the material’sthermal property. Material type parameters that may be identifiedinclude material composition (e.g., cotton vs polyester), thread counts,fabric density, spun/weave/stitch construction, and so on. In oneexample, some of the data in the storage medium 135 is stored on storagemedium in the measurement device 100 and some of the data in the storagemedium 135 is stored on a remote device.

FIG. 1D illustrates a functional block diagram of the device 100 thatwill be used throughout this description to describe variousconfigurations of sources and sensors for measuring differentnon-thermal (and thermal) properties of a material. The first member 110is connected to the second member 120 with clamping mechanism 130. Theenvironmental sensor 105 is illustrated as being disposed in the firstmember 100, however the sensor 105 may be in another location (evenexternal to the device 100). A source element 163 is disposed in thefirst member 110. In some examples, multiple source elements, providingdifferent types of stimulus (e.g., electromagnetic radiation, sound,vibration, compression, heat) will be present in an “array” of sourceelements. A sensor element 165 is disposed in the second member 120. Insome examples, multiple sensor elements, capable of detecting differenttypes of stimulus will be present in an “array” of sensor elements.

FIG. 1E illustrates a functional block diagram of an alternative device100′ that is a probe or wand that does not clamp around the materialsample, which will also be referred to as the material under test. Inthis example, the sensor element 165′ is disposed in the same member asthe source element 163. The examples illustrated herein in which thedevice is embodied as a clamp may be extended to include themodification illustrated in FIG. 1E wherever possible.

Electromagnetic Energy-Based Non-Thermal Material Properties

FIG. 2 illustrates an exemplary measurement device 200 that includesfirst member 210, second member 220, and clamping mechanism 230. Amaterial under test has been positioned between the first member 210 andthe second member 220 and the members are held in the closed position bythe clamping mechanism 230 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 205 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 200. The measurement device 200 utilizeselectromagnetic radiation (e.g., visible or non-visible light) todetermine a thermal property of the material under test. Anelectromagnetic radiation source element 263 is an LED operating innon-visible light spectrum (750 nm to 1100 nm), most likely 850-950 nm.The electromagnetic radiation source element 263 may be operated atconstant power, for brief periods of time, when controlled to do so bymeasurement circuitry (not shown).

A first electromagnetic radiation sensor element 265 a is a photodiodeplaced in axis of the emitted electromagnetic radiation. It is matched(receptive) to the wavelength of electromagnetic radiation emitted bythe electromagnetic radiation source element. Other wavelengths ofelectromagnetic radiation may be excluded. The output of the photodiodemay be converted into a voltage drop over it, or it could be aphotodiode system with CMOS that outputs a series of pulses having afrequency proportional to the electromagnetic radiation intensity itreceives. A second electromagnetic radiation sensor element 265 b isanother photodiode, operating at the same wavelength as electromagneticradiation sensor element 265 a. This diode is located off-axis, and sois not a direct measure of transmission/absorption, but rather measuresscatter. A third electromagnetic radiation sensor element 265 c isanother photodiode located along side, or behind the electromagneticradiation source element 263, and so that the third electromagneticradiation sensor element 265 c measures the backscatter from theelectromagnetic radiation source and/or material.

The electromagnetic radiation emitted by the electromagnetic radiationsource element 263 is not in the visible wavelength range so it is lessinfluenced by the color of the fabric through which it has to pass. Itis operated at constant current and voltage to ensure it emits aconsistent amount of electromagnetic radiation (consumes the same power)every time, and operates in the condition under which it was calibrated.In one example a electromagnetic radiation source of broad wavelengthcould be used that spans visible to non-visible IR electromagneticradiation (e.g., between about 300 - 1100 nm). The electromagneticradiation sensor elements should be configured to be receptive to thoseemitted wavelengths.

The electromagnetic radiation sensor elements 265 a-c are selected to bereceptive to the wavelength of electromagnetic radiation coming from theelectromagnetic radiation source element 263 in order to reduce theeffect of other influences. The various outputs of the sensor elementswill be recorded synchronously for a period of time of around 5 seconds(to allow for stabilization of readings) as illustrated in FIG. 2A. Analgorithm combines the response of the three electromagnetic radiationsensor elements to identify to the fabric type and/or thermal resistancethe fabric (as measured by an ASTM recognized machine configuration). Acorrelation will then be made between sensed values and thepredicted/approximated thermal resistance of the fabric. Another thermalproperty that may be determined by analyzing the electromagneticradiation received by electromagnetic radiation sensor elements isbreathability (similar to porosity) of the material under test.Breathability may be one factor used to determine the material’s type.

FIG. 3 illustrates an exemplary measurement device 300 that includesfirst member 310, second member 320, and clamping mechanism 330. Amaterial under test has been positioned between the first member 310 andthe second member 320 and the members are held in the closed position bythe clamping mechanism 330 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 305 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 300. The measurement device 300 utilizeselectromagnetic radiation to determine a thermal property of thematerial under test. A electromagnetic radiation source element 363 isan LED operating in non-visible light spectrum (750 nm to 1100 nm), mostlikely with a peak wavelength in the range of 850-950 nm. Theelectromagnetic radiation source element 363 will be operated at varyingpowers, such as a power sweep, as shown in FIG. 3A, for brief periods oftime, as controlled by the measurement circuitry (not shown).

First electromagnetic radiation sensor element 365 a is a photodiodeplaced in axis of the emitted electromagnetic radiation. It is receptiveto the wavelength of electromagnetic radiation emitted by theelectromagnetic radiation source element 363. Ideally other wavelengthsof electromagnetic radiation will be excluded preferentially. Output ofthe photodiode may be converted into a voltage drop, or the photodiodecould include a CMOS that outputs a sequence of pulses having afrequency that is proportional to the electromagnetic radiationintensity the photodiode receives. Second electromagnetic radiationsensor element 365 b is another photodiode operating at the samewavelength as the electromagnetic radiation source element 363. Thisphotodiode is located off-axis, and so is not a direct measure oftransmission/absorption, it measures scatter. Third electromagneticradiation sensor element 365 c is another photodiode located along side,or behind the electromagnetic radiation source 363, and so measures thebackscatter from the material sample.

The electromagnetic radiation emitted by the electromagnetic radiationsource element 363 is not in the visible wavelength range so it is lessinfluenced by the color of the fabric through which it has to pass. Theelectromagnetic radiation source element begins operation at the lowestpossible current to open the diode and increases up to the maximumoperating current of the diode over a couple of seconds (light powersweep). The sensor response from the first and second electromagneticradiation sensor elements 365 a, 365 b are monitored throughout toproduce two curves that are characteristic of the fabric under differentelectromagnetic radiation powers as shown in FIG. 3B. In one example aelectromagnetic radiation source of broad wavelength could be used thatspans visible to non-visible IR light (e.g., 300 - 1100 nm). Theelectromagnetic radiation sensor elements should be configured to bereceptive to those emitted wavelengths.

The sensor elements are selected to be receptive to the wavelength ofelectromagnetic radiation coming from the emitter in order to minimizethe effects of other influences. The various outputs of the sensorelements are recorded synchronously for a period of time of about 5seconds (to allow for stabilization of readings). An algorithm combinesthe response of the three electromagnetic radiation sensor elements toidentify to the fabric type and/or thermal resistance the fabric (asmeasured by an ASTM recognized machine configuration). In combinationwith other techniques taught herein various physical parameters of thematerial under test can be determined, and related to predicted thermalproperties. In a simple example, a correlation is made between thesensed values from the electromagnetic radiation-based system and thethermal resistance of the material.

FIG. 4 illustrates an exemplary measurement device 400 that includesfirst member 410, second member 420, and clamping mechanism 430. Amaterial under test has been positioned between the first member 410 andthe second member 420 and the members are held in the closed position bythe clamping mechanism 430 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 405 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 400. The measurement device 400 utilizeselectromagnetic radiation to determine a thermal property of thematerial under test.

Light source element 463 is an LED operating in non-visible lightspectrum (750 nm to 1100 nm), most likely 850-950 nm. Theelectromagnetic radiation source element 463 is operated at constantpower, for brief periods of time, as controlled by measurement circuitry(not shown). Instead of using photodiodes as sensor elements asillustrated in FIGS. 2 and 3 , sensor element 465 a is a digital cameramatched to the wavelength of the electromagnetic radiation sourceelement 463. A second sensor element 465 b, which may be a photodiode orphotodiode array, is included to measures the backscatter from thematerial sample.

Images of the back side of the material sample are recorded by thecamera 465 a and then passed to analysis circuitry (not shown) thatincludes vision/image interrogation software (such as Nationalinstruments Vision Development Module). As already discussed, theanalysis circuitry that executes the vision/image interrogation softwaremay be integrated into the measurement device or resident on a mobilecommunication device that receives image data (e.g., via a wireless orwired connection) from the measurement device.

The electromagnetic radiation emitted by the electromagnetic radiationsource element 463 is not in the visible wavelength range so it is lessinfluenced by the color of the material through which it has to pass.The electromagnetic radiation source element 463 is operated at constantcurrent and voltage to ensure it emits a consistent amount ofelectromagnetic radiation (consumes the same power) every time, andoperates in the condition under which it was calibrated. As outlined inFIGS. 4A and 4B, the image from the camera 465 a may be analyzed for anumber of things, such as the intensity at the center of the image (inaxis of the electromagnetic radiation source element), the exactgradient of transmission/adsorption/scatted profile. The pattern of thematerial structure (see FIG. 4C) will also be visible for matching tostored material patterns (e.g. whether the material is woven or spun,like weaved cotton or fleece, and so on). The absolute intensity of theimage can also be measured. The combination of features analyzed by thevision/image software will help to identify the material type, and itsthermal resistance (again as measured by an ASTM recognized machineconfiguration).

Mechanical Vibration-Based Non-Thermal Material Properties

FIG. 5 illustrates an exemplary measurement device 500 that includesfirst member 510, second member 520, and clamping mechanism 530. Amaterial under test has been positioned between the first member 510 andthe second member 520 and the members are held in the closed position bythe clamping mechanism 530 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 505 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 500. The measurement device 500 utilizesmechanical vibration in the form of acoustic energy or sound todetermine properties of the material under test that relate to a thermalproperty of the material under test.

In one example, the sound source element 563 is a speaker capable ofemitting sound from 20 Hz to 20 kHz (audible range). In some examples,the speaker operates above that sound frequency. In this example, thesound sensing element 565 a is a microphone with suitable response(matched to the speaker emission) placed in axis on the second member520 on the other side of the material sample under test. A second soundsensor element 565 b is an off-axis microphone that is used incollaboration with sound sensor element 565 a. An optional third soundsensor element 565 c detects backscatter sound, and may also be used toverify and validate various properties of the emitted sound and may alsobe used to allow for determination of phase shift when compared to otherdata received by the sensor elements 565 a and 565 b.

As illustrated in FIG. 5A the speaker 563 will emit a sweep offrequencies from 20-20000 Hz over a period of about 3 seconds and mayuse a constant or varying amplitude profile. In other examples, thespeaker 563 emits a “buzz” comprising single tone or chord, at afrequency (e.g., 20 KHz) which may be selected based on a type ofmaterial. At the point of emission the microphone system 565 a-565 c isinitialized and records sound as it is received after having passedthrough the material under test. Emission and received sound arerecorded synchronously, such that at any given point in time, it isknown at what frequency the emitter was resonating, and what thereceiver should have registered. From here is it possible to create anapproximate frequency/amplitude plot as shown in FIG. 5B (similar to theoutput of a Fast Fourier Transform (FFT) analysis), without having toperform an entire FFT. An FFT analysis of the entire recording may alsobe done to verify findings, but may not be required ultimately, savingexpensive processing power and vital time to execute analysis. In oneexample, data indicative of the emitted and recorded sound may be“exported” to a mobile communication device having sufficient processingresources to perform an FFT analysis of the sound data.

Data collected from the material under test may be operated on such thatthe frequency or time domain amplitude result is subtracted from apredetermined calibration constant. In one example, the thickness of thematerial sample is used to select the appropriate calibration data froma look-up table or similar regression, containing values of amplituderesponses from varying open gap conditions (i.e., without a materialunder test between the first and second members such that there is openair in the gap). FFT spectra recorded from the material under test maybe analyzed for peak and valley amplitudes and for the frequency-basedlocations of those features and in this manner compared to storedresults of similar analysis of FFT spectra recorded for different typesof materials to aid in determining a type of the material under test.The FFT spectra recorded from the material under test may be subject tointegral analyses, whereby the total value of the energy received by 565a and 565 b and/or 565 c is determined. The FFT spectra recorded fromthe material under test might be compared to previously recorded FFTspectra and shape and analyzed by checking for a match using comparisontechniques.

The sound response of material may be useful in probing the relativeporosity of the material (i.e., check that the material is not acontinuous plastic sheet, or a foil). The analysis circuitry shouldcorrelate the sound response to the breathability of the material, asthe material structure will influence the sound transmission,particularly where locally solid barriers are imposed (e.g., solids likefoil, plastic, and so on, that aren’t breathable).

In one example, the measurement device uses mechanical energy (e.g.,vibrations) to determine a non-thermal property of the material undertest. In this example, the source element 563 is a vibrator (e.g., anunbalanced motor vibrator, or electromechanical shaker) capable ofimparting physical motion to the material under test. The source element563 is capable of creating first harmonic vibrations in the 0 Hz-1 kHzregion. To ensure physical motion is adequately transmitted to thematerial under test, at least a portion of the material contactingsurfaces of 510 and 520 may include suitable surface roughness, suchthat the material under test is gripped and unable to move once theclamp is in the closed position. Therefore the clamp surfaces should notbe entirely ‘smooth’. The required surface roughness imparts a locallyhigh contact pressure to small elements of the fabric at the tips ofasperities, while maintaining the bulk compressing pressure in the rangeof 0.5 kPa to 1.5 kPa as controlled by the apparent area of contact andthe clamping mechanism 530. The source element 563 may also induce otherharmonic vibrations at higher frequencies. In this example, the sensingelement 565a′is a 3-axis accelerometer with suitable response (e.g.,matched to the energy emission) placed in axis on the second member 520.An optional third accelerometer element 565 c can be operable tosynchronously monitor the energy emission of the source element 563.

As illustrated in FIG. 5C the vibrator 563 may emit a sweep offrequencies from 0-1 KHz over a period of about 3 seconds. In anotherexample, the vibrator 563 may operate at a single frequency, ordiscretely step through various frequencies. At the point of emission,the accelerometer system 565 a-565 c is initialized synchronously andrecords displacement energy both as it is generated (565c) and as it isreceived after having passed through the material under test (565a, 565b). The properties of the material under test may directly influence theemission characteristics of the vibrator 563 and so recording theemitted energy using 565 c may be beneficial. Emission and receivedsound are recorded synchronously, such that at any given point in time,it is known at what frequency the emitter was resonating, and what thereceiver should have registered.

FIG. 5D shows the result of conducting Fast Fourier Transform analysison the recorded accelerometer data. Comparative differences in datareceived are related to physical properties of the material under test.For example, phase and frequency shifts relative to the emitted energycan be detected and attribute to properties of the material relating tothermal resistance. Analysis of higher harmonics measured at 565 a mayalso help to determine physical properties of the material under testthat relate to its thermal resistance. In another example, analysis ofthe data generated by accelerometers 565 a and 565 c may simply beevaluated for amplitude, and so results are indicative of the bulkattenuation of energy as a result of interactions with the materialunder test. In another example, accelerometers 565 a and 565 c may bereplaced by microphones to achieve a similar functionality.

Physical vibration of the material under test yields knowledge of themicrostructure composition under larger scale deformation than ispossible using acoustical energy alone. In particular, physicalvibration is good for probing vibratory deformation response at lowerfrequencies and higher amplitudes than acoustical energy alone. Thevibratory response of material may be useful in probing structuralproperties of the material. In one example, the detected responses mayrelate to stiffness, elasticity and material density which are functionof material composition (e.g., polymer, elastomer, cotton, and so on)and the construction type (e.g., weave, spun, infill, and so on) and allhave a role in the bulk thermally resistive properties of the materialunder test.

Coupling the material’s vibratory response to electromagnetic radiation,heat, or sound energy with thickness and compressibility data may createa scheme whereby the material’s type (e.g., fleece or cotton) can beidentified and its thermal resistance can be approximated/determined.Note that the pre-measured response of the system with the measurementdevice in the closed position may be subtracted from the measured testdata to remove background characteristics. The amplitude responsemeasured is both a function of interactions with the material structureand the path length of the sound energy transmission.

Compressibility-Based Non-Thermal Material Properties

FIG. 6A illustrates an exemplary measurement device 600 that includesfirst member 610, second member 620, and clamping mechanism 630. Amaterial under test has been positioned between the first member 610 andthe second member 620 and the members are held in the closed position bythe clamping mechanism 630 exerting sufficient pressure to contact thematerial under test without significantly compressing the material(e.g., applying a pressure between 0.5 kPa and 1.5 kPa). The clampingmechanism is configured to limit the pressure placed on the materialunder test to some predetermined amount (e.g., less than approximately1.5 kPA). The pressure may be controlled by a separate relief featuresuch as a spring arranged about a pivot point. An environmental sensor605 is configured to measure an environmental characteristic, such astemperature and/or humidity, of the environment surrounding the device600. The measurement device 600 utilizes mechanical energy stored insprings to determine the thickness and a thermal property of thematerial under test.

Mechanical source elements are spring-loaded wide-area contact elements663 a, 663 b. Spring-loaded wide-area contact element 663 a has a lowerspring constant/surface area combination than spring-loaded wide-areacontact element 663 b. Thus the wide-area contact element 663 a exertsless pressure on the material under test than the wide-area contactelement 663 b. Spring-loaded wide-area contact elements 663 a, 663 b mayhave lower spring constants than the clamping mechanism 630, but thereduced area of the wide-area contact elements as compared to the areaof the members 610, 620, allows the spring-loaded wide-area contactelements to apply a higher pressure than the clamping pressure in alimited portion of the material under test.

Distance sensor elements 665 a, 665 b (e.g., linear variable resistorsin some examples) measure the extension of both springs 663 a, 663 b.Distance D1 is the extension of the spring with low spring constant (orlarger contact element area) which exerts lower pressure. Distance D2 isthe extension of the spring with high spring constant (or smallercontact element area) which exerts higher pressure. A third angle or gapcorresponds to the angle between the first member 610 and the secondmember 620 when the measurement device is in the closed position andcontacting (without significantly compressing) the sample material. Thegap is measured by a variable resistor 665 c that is attached to theclamping mechanism. The voltage drop across the resistor is related tothe angle.

To correlate the thermal properties of the material sample, the gap isderived from the reading coming from the rotation of the pivot of theclamping mechanism 630. Voltage drop across the resistor is measured andcorrelated to the absolute gap from the material under test.

When the measurement device 600 is closed around the material sample,the two spring loaded wide-area contact elements 663 a, 663 b (notethese provide surface areas creating elements of local pressure) arepushed against the material sample applying different pressures. Thelower pressure wide-area contact element 663 a compresses further thanthe higher pressure wide-area contact element 663 b, and so thedisplacement of the two can be correlated to the compression of thematerial sample (e.g., based on a ratio or similar).

Note that the role of the spring-loaded wide-area contact element 663 acould be combined with the spring load of the clamping mechanism 630 -such that the spring load of the clamping mechanism (light load) is thespring load of wide-area contact element 663 a and so the gapmeasurement is actually distance D1. Distance D2 may be still used todetermine compressibility. Essentially, from knowing displacement datafrom any two locations under different pressures, compressibility can bedetermined for those prescribed conditions as shown in FIG. 6B. Thecompressibility as measured by the measurement device could becalibrated to a given displacement under a given pressure, or simply usea curve fit, or regression type relationship to help identify thematerial and its thermal resistance based on displacement data.

Many other mechanical arrangements (e.g., linkages, pivots, slides, andso on) and sensors may be utilized to determine the compressibilityprofile of the material under test. For example, the reactive force inthe spring wide-area contact elements 663 a, 665 a could be correlatedto the gap. The relative displacement of the wide-area contact elements663 a, 663 b could also be determined using variable resistors, linearvariable differential transformers, hall sensors, eddy currents, lasertime-of-flight and/or capacitance based systems.

FIGS. 6C and 6D illustrate an alternative example of a measurementdevice 600′ in which the clamping mechanism 630′ includes a small servomotor 632 mounted at the hinge pivot location marked by P. For thepurposes of this description, the term servo motor is a shorthandreference for any suitable motor, including position encoded motor,controllable motor with feedback, and so on. The servo motor may be usedinstead of or in addition to spring mechanisms in the clampingmechanism. The user places the material under test in between first andsecond members 610′ and 620′ and the measurement system is activated.The servo motor 632 closes the device 600′ until the servo motor 632detects contact with the material under test. Contact with the materialsample may be done by sensing electromagnetic radiation. For example,the device 600′ includes a electromagnetic radiation source element 663′and electromagnetic radiation sensor element 665 a′. The measurementcircuitry may be configured to determine when the electromagneticradiation source sensor 665 a′ is blocked by contact with a solid(near-zero backscatter). The electromagnetic radiation source element663′ and electromagnetic radiation sensor element 665′ may also be usedto measure the thermal property of the material sample as described inFIGS. 2-4 , but operated at a low power to detect contact. Contact withthe sample could also be determined by mechanical sensor element 665 b′,which may measure strain, pressure or bending (for example) of the firstmember 610′ which would change with contact. Proper contact with thematerial sample may be verified throughout the measurement process.There are various possible methods of determining contact.

Once contact with the sample is determined, the thickness can be gaugedthrough knowledge of the servo motor position (pre calibrated, so usinga lookup table for servo position vs gap). This is the uncompressedvalue of thickness. Other measurements from the various sensor arrayscould be conducted here, in particular this location would be useful forthe thermal system, where contact needs to be light, but definitely incontact. From this ‘first contact’ location, the servo motor couldadvance a known amount, thus compressing the material. Pressure measuredby mechanical sensor element 665′ could be used to determine the gap vs.pressure which would equate to compressibility. Measurements at 2 ormore locations may be taken, as shown in the example data of FIG. 6D.This technique may provide advantages over the spring method describedin FIGS. 6A-6B as it combines a measure of compressibility and thicknessinto one, and allows for more control over the clamp contact.

In one example, a strain gauge may be used to measure the reactive forceacross the clamping mechanism between the spring load and thematerial-spring load. Compressibility can be approximated by determiningthe reactive force of the material at a given spring rate provided bythe clamping mechanism.

Thermal Energy-Based Material Properties

The material property measurement devices illustrated in FIGS. 1-6utilize non-thermal energy such as electromagnetic radiation, sound, andmechanical energy, to determine a property of a material sample such asthickness, compressibility, thermal resistance, or material type. Usingnon-thermal energy to determine a property of a material provides manybenefits including reduced power consumption, fairly quick measurementand analysis, and possibly some packaging advantages that make ahandheld measurement device more feasible. FIG. 7 illustrates anexemplary measurement device 700 that uses thermal energy to determine athermal property of a material sample. In spite of using heat, themeasurement device 700 is suited for household use, portable, andcapable of being held in hand as compared to laboratory thermalresistance measurement systems which are large, expensive, and slow.

FIG. 7 illustrates an exemplary measurement device 700 that includesfirst member 710, second member 720, and clamping mechanism 730. Amaterial under test has been positioned between the first member 710 andthe second member 720 and the members are held in the closed position bythe clamping mechanism 730 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 705 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 700. The measurement device 700 utilizes heat todetermine a thermal property of the material under test.

Heat source element 763 is a heated plate. In one example, the heatsource element 763 is a highly resistive wire that heats quickly whencurrent is applied. The thermal mass of the heat source element 763should be small, so it can heat up quickly with little thermal inertiaand robust enough such that it operates consistently over repeated use.A heat sensor element 765 is a thermocouple or other temperaturemeasurement device with suitable response and accuracy precision (suchas TMP36, thermocouple, infrared sensor, resistance temperaturedetector, and so on). The heat source element 763 and heat sensorelement 765 are loaded against the material with a known and constantpressure coming from the clamping mechanism. Second member 720 includesinsulated backing material indicated by the shading. The insulatedbacking material could be any insulator, most likely plastic/air thatsurrounds the heat source element 763 and should be sufficiently sizedto adequately limit the influence of the ambient environment onperformance.

During measurement, the heat source element 763 is fed a controlledburst of energy from a power supply (battery) as shown in FIG. 7A. Theheat sensor element 765 is mounted in the first member 710 and so isspring loaded against the material. The distance between the heat sourceelement 763 and the spring loaded heat sensor element 765 is a functionof the first compressibility of the material. The clamping mechanismputs the temperature measurement device in contact with the top of thematerial under test sample. The heat sensor element 765 should be anarea-type sensor (e.g., having sufficient area). The heat sensor element765 should not be a point-probe type, as it should be measuring thetemperature rise of an area of material, to remove the effect ofnon-homogeneity in the material. Both heat source element 763 and heatsensor element 765 should operate over an area, for example, of 20 mm²min in order to accurately and representatively capture the thermalresistance of the material under test.

Voltage/data from heat sensor element 765 (see FIG. 7B) is measured andcorrelated to the thermal resistance of the material under test(calibrated beforehand using an ASTM recognized instrument). Analysiscircuitry (not shown) may store and read a look-up table orregression/curve fit that maps the gradient of the temperature data ascorrelated with thermal resistance (see FIG. 7C). In one example, anamount of time taken to pass a threshold temperature is measured, whichapproximates a gradient. Note that a measure of thickness andcompressibility may help correlate this method to thermal resistance,although thickness and compressibility is not required for a simpleapproximation.

Using this thermal measurement technique alone or in combination withanother non-thermal measurement technique provides several benefits. Forexample, the thermal measurement technique measures the thermalresistance of the entire insulation layer (not just what the sensorelement touches). By having the temperature sensor on the other side ofthe material (relative to the heated bed), if the material were to becomposed of multiple layers, the entire composite thermal resistance ismeasured. The thermal measurement technique measures more than justconductance, a property that can dominate with reflectance methods liketransient hot plate, and other one-sided touch/measure implementations

One sided methods can struggle with thin samples (e.g., clothing) andmay produce erroneous results when a foreign object (or a significantair gap) is inadvertently in contact with the sample. However, thedescribed measurement device includes first and second members thatcontact both sides of the sample, reducing the risk of a foreign objectbeing included in the measurement.

In the device 700 the heat sensor element 765 on the other side of thematerial/heater moves with the thickness and the thickness can bemeasured. Thus the distance from heated plate to thermocouple will varydue to thickness and the thermal measurement technique will not includean air gap that would have to be calibrated out. With this methodacceptable data can be obtained with just one heat burst (note that withtransient plane more than three repetitions are recommended).

The thermal measurement technique is easily combined with otherabsorption/transmission measurements, like electromagnetic radiation andsound. The thermal measurement technique can easily be achieved with asimple heater and temperature measurement device and can be implementedwith less expensive, low precision electronics. This is in contrast totransient plane type one-sided methods that are reported to require veryhigh precision resistance measurement devices for temperaturemeasurement and heat control. Because thermal resistance is measuredalong with thickness and other non-thermal data, partial materialidentification is possible (unlike transient plane method). For example,a material sample with a certain gradient temperature rise, and knownthickness can be correlated to a fleece, or a cotton sack, ordifferentiated from another material with the same thickness butdifferent gradient for example.

If a thermocouple (or other similar temperature measurement device) isadded to the heater plate, the measurement system could double check theamount of energy provided to the heater, and would improve precision forlittle cost. Data from this sensor could be used in the calibrationscheme. The thermocouple could also be used as a temperature probe whenthe measurement device is fully opened as illustrated in FIG. 1E. Thefirst member may be held against a surface to measure a temperature ofthe surface (e.g., a person’s forehead, an outside surface of a sleepsack, and so on).

In a first calibration scheme, gradients of temperature rise arerecorded for known thermal resistance materials. Results from materialsunder test are compared to that data (or a regressed fit of it) andmatched to an equivalent thermal resistance value. A database ofmaterials is accessed to identify a material that has that gradientvalue, and that thickness, and see if a match exists that identifies itsprobable structure (polyester fleece vs bamboo weave, for example).

In a second calibration scheme a series of calibrations are taken atdifferent device gap settings (a priori), with only air between theheated plate and thermocouple, at a selection of ambient conditions. Thetemperature reading initially taken prior to the heat burst is used toselect a calibration profile, or interpolate between using a fit. Therecorded value of temperature rise variation with respect to time(gradient) is subtracted from the calibration gradient to give thethermal resistance gradient of the material under test. This value isthen compared to a calibration to determine the absolute thermalresistance of the material.

For example, the thermal resistance of material under test may bedetermined as T_(Res) (air at same gap) - T_(Res) measured. Thistechnique is especially useful for thermal resistance values greaterthan 0.3 (Km²/W). If a higher temperature difference is created byincreasing energy burst per unit time data quality will likely improve.

FIG. 7D shows the apparatus 700 with the clamping mechanism 730 in thefully open condition. This exposes the temperature measurement sensor765 and allows the entire assembly to be held against a material undertest (or the skin of a person) by the user, rather. This allows thedevice to be used as a temperature measurement probe. In one example,the device 700 is temporarily used in the open-hinge condition tomeasure the temperature of the exterior surface of a material (sleepsack or similar) while in occupancy. Swiping the temperature measurementdevice 765 over an area of the exposed material for a short period oftime (1-10 seconds) and collecting various statistical parameters (e.g.maximum, minimum, median, and mean temperatures) allows for accuratedetermination of the external surface temperature conditions. In oneexample, instead of a thermocouple, a thermal imaging system is used todetermine the temperature of the surface under test and/or thetemperature of the occupant.

The external temperature values may be operated on with the currentambient room temperature value, the measured or assumed internaltemperature of the material and the predetermined thermal resistancevalue of the material under test. Algorithms designed to calculate theheat flux conditions may then be used to determine if existing heat-losscondition is within acceptable, predetermined, and preprogrammed limits.The results may be presented to the user along with recommendationssuggesting better clothing material, layette, or ambienttemperature/condition choices.

In the simplest case, data detailing the temperature condition of thematerial external to the occupant, or the occupant itself may be used toprovide recommendations to the caregiver, in absence of the knowledge ofthermal resistance values. In one example, where an occupant is shown toregister a body temperature in excess of predetermined limits,recommendations could be made to check the occupant for signs of afever, or to simply try a less insulative clothing selection.

Conductance-Based Non-Thermal Material Properties

The moisture content of a material sample may significantly impact itsthermal properties as well as comfort in wearing the material sample.Therefore, it may be useful for the measurement device to be able todetermine the moisture content of the material sample. FIG. 8illustrates an exemplary measurement device 800 that includes firstmember 810, second member 820, and clamping mechanism 830. A materialunder test has been positioned between the first member 810 and thesecond member 820 and the members are held in the closed position by theclamping mechanism 830 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 805 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 800. The measurement device 800 utilizeselectrical conductance to determine the moisture content of the materialunder test.

Electrical source elements first and second electrodes 863 a, 863 b aredisposed in first member 810 so that the electrodes contact a materialsample. An electrical sensor element ohmmeter 865 measures aconductivity of the material as a function of the resistance between thetwo electrodes 863 a, 863 b, which are held at fixed distance from eachother, as current tries to pass in between. As an alternative toelectrodes, the electrical source elements 863 a, 863 b could be probes,or a plate type configuration (such as a swirl printed onto a flat). Inone example, a capacitance method can be used for measuring moisturecontent of the material by probing the dielectric properties of thematerial.

During moisture content measurement, the first and second electrodes 863a, 863 b are put in contact with the material under test by the springpressure provided by the clamping mechanism 830. The resistance of thematerial is measured by providing constant current to the electrodes. Asshown in FIG. 8A, the conductance/resistance of the material varies withmoisture content.

Different materials inherently have different conductivity/resistivityand so the measured resistance could be used in collaboration/synergywith other measurement techniques discussed herein to help identify amaterial-type, as well as a material’s thermal resistance. Moisturecontent might influence the electromagnetic radiation and soundpropagation and so the resistance measure might be used to correct datacollected from those sensor systems. In one example, the moisturecontent test is used as a pass fail criteria displayed on themeasurement device, and not necessarily for precision identification. Inthis manner the moisture content measurement may be a check that thematerial is not too wet for use. The material’s conductivity may also beused to determine that the material under test does not containuncomfortable (e.g., metallic, foil) elements and provide an alert whenthe conductance indicates an uncomfortable material is being tested,regardless of the thermal property that is determined.

In addition to the thermal properties of a garment or blanket worn by ababy during sleep, the hardness of a sleep surface is also an importantconsideration for a caregiver. When the measurement device is used by acaregiver, it may also be advantageous for the measurement device toalso be capable of determining a softness or hardness (in terms ofelasticity) of a surface and display information related to thesuitability of the surface for sleeping babies.

FIG. 9 illustrates an exemplary measurement device 900 that includesfirst member 910, second member 920, and clamping mechanism 930. Amaterial under test has been positioned between the first member 910 andthe second member 920 and the members are held in the closed position bythe clamping mechanism 930 exerting sufficient pressure to contact thematerial under test without significantly compressing the material. Anenvironmental sensor 905 is configured to measure an environmentalcharacteristic, such as temperature and/or humidity, of the environmentsurrounding the device 900. The measurement device 900 utilizes one ormore source elements 963 and sensor elements 965 and measurementtechniques described with reference FIGS. 2-7 to determine a thermalproperty of the material under test.

To measure the softness of a surface, the device 900 includes adurometer mechanism 990 extending from an outside surface of one of thesecond member 920. The durometer mechanism includes a spring 993 havinga predetermined spring constant and a probe 995 disposed at a distal endof the spring 993. Measurement circuitry (not shown, see FIG. 1C) isconfigured to determine durometer data based on a compression of thespring. Analysis circuitry (not shown, see FIG. 1C) is configured todetermine a surface suitability based on the durometer data and displayinformation related to the surface suitability.

A spring loaded switch (not shown) in the durometer mechanism iscompressed as the probe 995 is pressed onto the surface. If the probe995 is loaded against a surface and the spring 993 could not becompressed enough to close the switch, the material would be classifiedas being too soft. If the spring 993 could be compressed enough to closethe switch, the material would be classified as being suitable forsleep.

While the preceding description illustrates various examples of themeasurement device including a single thermal property measurementtechnique (e.g., non-thermal measurement techniques usingelectromagnetic radiation, sound, mechanical energy, electrical energyas well as thermal energy techniques), in some examples, the measurementdevice includes source elements and sensor elements for multiplemeasurement techniques. Data from the various measurement techniques maybe combined to determine a thermal property of the material, classify amaterial type, and/or determine the suitability of material for a givenenvironment. A multi-variate space (e.g., embodied in a lookup table ormathematical correlation expression) may be used to map data values fromvarious measurement techniques to a single thermal resistance and/ormaterial identity type.

While an environmental sensor element is included so that a garment’ssuitability with respect the present environment, in some situations, acaregiver may want to select a garment that is suitable for a differenttemperature/humidity. For example, when a caregiver is going to take ababy to a park, the caregiver may use the device to enter a predictedtemperature. The analysis circuitry then determines the suitability ofthe tested garment for the entered temperature and/or displays storedgarments having thermal properties mapped to the entered temperature. Inanother example, the device may access weather information and providethe predicted temperature to a user or automatically use the predictedtemperature for the suitability analysis.

The type of material may affect how measured non-thermal or thermal datamay map to a thermal resistance. Therefore determining the type ofmaterial may be useful in improving the accuracy with which a thermalresistance is determined using the above described techniques. The ploton the left side of FIG. 10 illustrates how an electromagnetic radiationprofile varies according to material types, meaning that the profilescan be used to classify types of materials. The graph on the right FIG.10 illustrates an example of how a combination of electromagneticradiation and acoustic measurement data as well as a measured thicknessof the material can be used to classify a material type. Othercombinations of profiles measurement data could be used to identifymaterial type. At the bottom of FIG. 10 , image data taken by a cameraas described in FIG. 4 can be used to identify patterns characteristicof fleece as compared to woven cotton.

For the purposes of this description, the term “material,” “materialsample,” “fabric,” “material type,” “fabric type,” or “garment” shouldbe construed as including a single layer of a homogeneous material; acomposite material that includes more than one component; a layeredarticle that, as manufactured includes layers of different materialtypes (e.g., nylon shell overlaying a fiber fill); or a collection oflayers of materials stacked together by a user of the measurementdevice. The measurement device may determine the thermal property of anymaterial sample that it contacts, regardless of the layers or differingcomponents of the material. Recall that the measurement device may alsobe able to combine separate measurements made for different separatelayers of a layette or outfit into a composite thermal property value.

FIG. 11 illustrates a flow diagram outlining an exemplary method 1100for determining a thermal property of a material sample with ameasurement that includes a first member and a second member. At 1130the method includes applying non-thermal energy to a first side thematerial sample using a source element on the first member. At 1140 themethod includes sensing, with a sensor element on one or both of thefirst member and the second member, a response of the material sample tothe non-thermal energy. At 1150 the method includes generating, with themeasurement device, non-thermal data indicative of the response. At 1160the method includes determining a thermal property of the materialsample based on the non-thermal data. Examples of non-thermal energyinclude electromagnetic radiation, sound, mechanical, and electrical.

As discussed above, determining a suitability of a given material for agiven environment can be helpful to a caregiver of an infant, baby,child, teen, or adult incapable of providing feedback on their comfort.FIG. 12 illustrates a flow diagram outlining an exemplary method 1200for providing suitability feedback to a user of a device. The methodincludes, at 1210, providing, in a measurement device, a storage mediumhaving thermal property values mapped to ranges of environmentcharacteristic values. At 1220 the method includes determining, with themeasurement device, a sample thermal property value of a materialsample. Any combination of the measurement techniques described in FIGS.2-9 can be used to determine the thermal property value.

At 1230 the method includes determining, with the measurement device, aenvironmental characteristic value (e.g., a temperature and/or humidityof the room in which the device is present). In one example, the devicemay receive a temperature/humidity entered by way of a user interfacedisplayed on the indicia circuitry (including, optionally, a connectedmobile communication device). At 1240 the method includes reading thestorage medium to determine if the environmental characteristic valuefalls within a range of environmental characteristic values mapped tothe sample thermal property value. At 1250 the method includesdisplaying a positive suitability result when the environmentalcharacteristic value falls within the range of environmentalcharacteristic values mapped to the sample thermal property value.

FIG. 13 illustrates a flow diagram of an exemplary method 1300 that maybe performed by a measurement device as described above. At 1302 themethod includes taking benchmark/background measurements. At 1304 adetermination is made as to whether all systems are in good workingorder. If not, at 1308 the device displays an indication that the deviceis not usable. When the device is determined to be functioning properly,at 1306 the method includes recording environmental data (e.g.,temperature/humidity). At 1310 the method includes displaying savedgarment options having thermal resistance values appropriate for theenvironmental condition. If no garment is appropriate or the userchooses to continue without selecting a saved garment, at 1312 themethod includes prompting the user to place the sample material withinthe first and second members of the device. At 1314, the method includesexecuting all sensor systems to perform one or more measurementtechniques.

At 1320 a determination is made as to whether the moisture content ofthe garment is above a specified limit. If so, at 1322 the methodincludes reporting (via indicia circuitry) that the material is too dampfor comfort. If the material is not too moist, at 1324 a determinationis made as to whether electromagnetic radiation penetrates the samplematerial. If electromagnetic radiation does not penetrate, meaning itmay be non-breathable, at 1326 the device reports that the material maynot be comfortable. At 1327, the method includes analyzing the thicknessand compressibility of the material to determine whether the material is“thick” or “thin” based on some predetermined limits on thickness. Ifthe material is thick, at 1328 data from the sound and thermal systemsare selected. If the material is thin, at 1330 data from theelectromagnetic radiation and thermal systems are selected. At 1332, theselected data is corrected/correlated based on thickness andcompressibility. At 1334 a material type is identified and displayed forthe user to confirm. At 1336 the suitability of the garment is reportedand at 1340 the user is prompted to save the item of clothing, mapped tothe determined thermal resistance, for future access. At 1338, themethod includes other functions such as displaying educational messagesor prompting the user to measure the softness of the sleep surface.

FIG. 14 illustrates an alternative method 1400 that may be performed bythe thermal property measurement device described herein. At 1402 themethod includes taking benchmark/background measurements. At 1404 adetermination is made as to whether all systems are in good workingorder. If not, at 1408 the device displays an indication that the deviceis not usable. A system status check could include an “open air” test ofthe device (e.g., with no material sample within the members). Sensorvalues can be compared with stored values to determine that all systemsare functioning properly.

When the device is determined to be functioning properly, at 1405 themethod includes recording environmental data (e.g.,temperature/humidity). At 1410 the method includes displaying savedgarment options having thermal resistance values appropriate for theenvironmental condition. If no garment is appropriate or the userchooses to continue without selecting a saved garment, at 1406 themethod includes prompting the user to place the sample material withinthe first and second members of the device. At 1412 the method includestaking thickness and compressibility measurements of the material. At1414, the method includes executing remaining sensor systems to performone or more measurement techniques as determined based on the thicknessand compressibility.

At 1420 a determination is made as to whether the moisture content ofthe garment is above a specified limit. If so, at 1422 the methodincludes reporting (via indicia circuitry) that the material is too dampfor comfort. If the material is not too moist, at 1424 a determinationis made as to whether electromagnetic radiation penetrates the samplematerial. If electromagnetic radiation does not penetrate, meaning itmay be non-breathable, at 1425 the device reports that the material maynot be comfortable. At 1426 the method includes analyzing collected dataand determining a calibration scheme to use. At 1432 the collected datais corrected or correlated based on the calibration scheme determined at1426. At 1434 a material type is identified and displayed for the userto confirm. At 1436 the suitability of the garment is reported and at1440 the user is prompted to save the item of clothing, mapped to thedetermined thermal resistance, for future access. At 1438, the methodincludes other functions such as displaying educational messages orprompting the user to measure the softness of the sleep surface.

FIG. 15A illustrates an exemplary measurement device 1500 that utilizesarrays of source elements and sensor elements to perform severalmeasurements including non-thermal measurements on the material undertest. The device 1500 includes first member 1510, second member 1520,and clamping mechanism 1530. A material under test has been positionedbetween the first member 1510 and the second member 1520 and the membersare held in the closed position by the clamping mechanism 1530 exertingsufficient pressure to contact the material under test withoutsignificantly compressing the material. The measurement device 1500includes a first array 1561 of source elements 1563 a, 1563 b, 1563 c 1,and 1563 c 2 mounted in the first member 1510 and he second member 1520includes a second array 1567 of sensor elements including 1565 a and1565 b 1. The measurement device 1500 includes an electromagneticradiation measurement system with electromagnetic radiation sourceelement 1563 a and electromagnetic radiation sensor element 1565 a, avibration measurement system with vibrator element 1563 b andaccelerometers 1565 b 1, 1565 b 2, and a compression measurement systemwith spring-loaded wide-area contact elements 1563 c 1, 1563 c 2 anddistance sensor elements 1565 c 1,1565 c 2.

To determine a thermal property of the material under test, as describedabove in more detail in the separate sections for each measurementtechnique, the measurement device 1500 activates electromagneticradiation source element 1563 a measures electromagnetic radiationpassing through the material sample with electromagnetic sensor element1565 a. The measurement device 1500 activates vibrator element 1563 bmeasures a mechanical response of the material sample with accelerometer1565 b. The measurement device 1500 measures the compressibility of thematerial sample using distance sensor elements 1565 c 1, 1565 c 2. Thedifferent measurements may be performed simultaneously or according tosome sequence.

In addition to the illustrated combination, the source elements in thearray 1561 may include sources capable of emitting electromagneticradiations such as infrared, heat and visible light, a speakerconfigured to emit acoustic radiation such as sound or mechanicalvibrations, and mechanical members configured to apply physical pressure(e.g., for measuring compression). The array 1561 in the first member1510 also includes sensor elements 1565 b 2, 1565 c 1, and 1565 c 2.

In addition to the illustrated combination, the sensor elements mayinclude sensors required to measure displacement such as hall effect,capacitance sensors, resistive sensors, lasers or strain gauges. Thesensor elements may also include force measuring sensors,accelerometers, microphones, temperature measuring devices, photodiodes,photodiode arrays, photoresistors, capacitance probes, and variousspectrum cameras. The arrays 1561, 1563 may be controlled tosimultaneously, or according to some predetermined sequence, activatethe source elements and the sensor elements. The arrays 1561, 1563 mayinclude source elements and sensor elements associated with any of themeasurement techniques described above in addition to or instead of thesource elements and sensor elements illustrated in FIG. 15A.

FIG. 15B illustrates a flow diagram outlining an example method 1570that may be used by a measurement device that includes multiplemeasurement techniques as with the device 1500 of FIG. 15A. At 1572, themethod includes attaching the device to the material under test. At1574, the method includes executing non-thermal measurement systems(e.g., electromagnetic radiation, vibration, compression, and so on). At1575, the method includes determining a thermal resistance value andmaterial type based on the measurement data from the various non-thermalmeasurement systems. At 1576, the method includes determining acertainty of the thermal resistance value and material typeidentification. This may be performed by determining a fit between themeasurement data from the different measurement systems and storedmeasurement data for the determined thermal resistance value andmaterial type (see, e.g., FIG. 10 ). At 1577, a determination is made asto whether the certainty is above a threshold. If not, at 1578 themethod includes executing a thermal measurement system and at 1580 alldata (including thermal data if obtained)) is used to determine thermalresistance and material identification. At 1582, the method includesadding the thermal resistance to a thermal resistance of any previouslymeasured layers.

At 1583-1585 a temperature input is selected for determining thesuitability of the material is determined using one or more options inparallel. At 1583 an external temperature input (not from an onboardsensor) is received for use to determine suitability. At 1584 theambient temperature is measured by an onboard sensor. At 1585 a bodytemperature or inner sleep sack temperature is either measured orreceived. At 1586, the method includes comparing the selectedtemperature input with the thermal resistance value. At 1592, the methodincludes providing a recommendation to a user (e.g., whether or not thematerial layer(s) provide a suitable thermal resistance for the selectedtemperature input). At 1590, the method includes automatically affectinga change to the environment to make the environment more suitable forthe thermal resistance (e.g., adjusting thermostat).

FIG. 15B shows that data collected by the device may be operated onsimultaneously or synchronously using a variety of algorithms to relatephysically measured parameters to thermal resistance approximations.Data from the system in its entirety provides information relating tothe physical properties of the material under test such as, fiber type,fiber size, fiber blend, thickness, compression ratio, density, surfaceimpedance, conductance, elasticity, airflow resistance and porosity.Thermal resistance is a function of the physical composition andmicrostructure of the material(s) under test and so correlating datafrom various measurements probing these physical properties to thermalresistance is possible using non-thermal techniques. Where determinationis not possible, above a previously specified threshold value, a thermaltechnique is deployed. Data from this system will be noisy as measuringheat-flux in non-laboratory conditions is not ideal. However, this datacombined with the data from the other non-thermal inputs allows for theacceptable threshold to be exceeded and determination of the predictedthermal resistance of the material under test to be reported. At thispoint the predicted thermal resistance values can be added to previouslymeasured thermal resistance values if a layette is being created.

In one example, the system compares the predicted thermal resistancevalue of the material under test with others stored in a database andprovides recommendations of multiple possible layering options thatcould match the predetermined ambient condition ensuring that the entireclothing ensemble is thermally matched for the ambient conditions inwhich it is to be deployed. In another example the system operates basedon knowledge of environmental conditions alone and does not need to testa material. It compares the predicted, measured or otherwise inputtedenvironmental conditions with a database of clothing detailing recordedthermal resistance values and creates multiple clothing options for theuser to choose from. In this way the clothing ensemble can be selectedby the user, allowing for style or other preference to be observed,while still optimally matching the thermal resistance of the layette forthe environment in which is it will ultimately be deployed.

The device may operate based on temperature measurements taken from thelocal environment using its onboard systems, or using external inputsregarding predicted weather, or from manual user inputs can be used inthe comparison to the measured thermal resistance values. Comparison canalso be made from other temperature measurements provided to the systemwhich may be a measured core body temperature, or the currenttemperature inside a sleep sack, for example. Input values of ambientconditions are ultimately compared with predicted thermal resistancevalues, and recommendations are provided to the user. In one example,the system automatically updates a thermostatic control system using theresult of the comparison to ensure the ambient conditions within thelocal environment are matched to the thermal resistance of the selectedlayette. In another example, after the baby is dressed the measurementdevice may be clipped to a car set or stroller so that the ambienttemperature continues to be measured and compared to the last determinedthermal resistance. When the ambient temperature falls outside the rangemapped to the thermal resistance, a temperature alert may be provided byindicia circuitry.

FIG. 16 illustrates several examples of displays/user interfaces thatmay be presented on indicia circuitry (e.g., on the measurement deviceor on a mobile communication device as illustrated). Example ‘a’indicates that a caregiver has the room temperature set too cold forcomfortable sleep, even though the thermal property of the selectingclothing’s material is suitable for the temperature. Example ‘b’indicates that a caregiver has the room temperature set too hot forcomfortable sleep, even though the thermal property of the selectingclothing’s material is suitable for the temperature. Example ‘c’indicates that the caregiver has the room temperature set in anacceptable range and has selected a garment or garments that aresuitable for comfortable sleep. Example ‘d’ displays the result of thecaregiver selecting clothes that would not provide sufficient thermalresistance for the ambient temperature. A recommendation is given to trysomething that would make the baby warmer. Example ‘e’ displays theresult of a caregiver testing a garment that would overdress the babyfor the ambient temperature. The caregiver is advised to try clothingthat would make the baby cooler.

In examples ‘c’-‘e’ a “normalized” representation of the thermalsuitability of the measured garment for the present environment isdisplayed as a number in which 1.0 indicates a “perfect” match betweenthe garment and the environment. In example ‘d’ the normalizedrepresentation is 0.5 which indicates that the garment is insufficientlywarm. Likewise in example ‘e’ the normalized representation is 2.5 whichindicates that the garment is significantly too warm for theenvironment.

FIG. 17 ‘a’ reports a game-based trend of the suitability of clothingselected by the caregiver over a period of time to show improvement andgamify the suitability interaction. This feature records a caregiver’sgarment suggestions and compares the thermal resistance of the suggestedgarments to the room temperature. A score is given in relation to howclose the thermal resistance of the suggested garment is to an idealthermal resistance. Scoring trends are determined based on stored usagedata and a “ranking” is determined based on the score. Example ‘b’reports a quantification of the improvement in a baby’s sleep obtainedby choosing suitable clothing and maintaining optimal room temperature.In order to use this feature, the user may be prompted to quantify thequality of sleep or other parameter on a periodic basis so that thequality quantification may be correlated with the suitability of theselected garment. This will cause recordation of the quantification inusage data as shown in FIG. 1C. FIG. 17 ‘c’ displays an example ofpotential education provided to the user to remind them of the most upto date recommended sleep practices.

In one example education is delivered to the user based on specificlearnings made through operation of the device. Where recordedhistorical data suggests a preference to overdress an infant exists,education would be selected and administered explaining the dangers ofoverdressing and helping the user to improve their clothing or layetteselection skills. In another example, where it is inputted that thedevice is being used with a premature infant, specific educationtailored to those conditions might be administered. If it is determinedthat the device is constantly being deployed in an environment that isbelow or above predetermined acceptable environmental limits it maysuggest changes need to be made to the sleep environment itself.Education articles may be selected through interrogation of any of thedata handled by the device, including ambient conditions, clothingselections, user inputs, external inputs, predictions and forecasts andusage statistics.

An example user interface or display that is not illustrated in FIG. 17is a thermal resistance alert feature. This feature provides an alert ifthe room temperature changes outside of range of temperatures mapped tothe most recent thermal resistance and displays an alert message to theuser. To support this feature the device continues to measure (orotherwise determine) the ambient temperature around the device withoutperforming thermal property assessments. Each new ambient temperature iscompared with the range of temperatures mapped to the last recordedthermal property value (or selected garment’s thermal property value).When the new ambient temperature is outside the range, the alert(visual, audio, or both) is provided.

Another user interface or display that is not illustrated in FIG. 17 isa database of personalized clothing recommendations. This featureprompts the user to capture an image of a measured garment and recordsthe measured thermal resistance mapped to the image of the clothingarticle in a database. The next time the room temperature is taken or anew temperature is predicted (e.g., from a weather forecast or the usermanually inputting the predicted temperature), the database is searchedfor a garment of acceptable combinations of garments and sleep sackshaving a suitable thermal resistance for that temperature. In oneexample, the database is constructed externally to the user and containsgeneric material and/or thermal property information relating topotential material and/or clothing choices. Comparison is then madebetween the material properties remote database and the predicted,measured or otherwise inputted environmental conditions and subsequentrecommendations provided to the user.

Another user interface or display that is not illustrated in FIG. 17 ispersonalized learning. Personalized learning includes the user recordingthe thermal resistance of the clothes selected and the room temperature,and then is prompted to enter an experienced quality characteristic(e.g., a rating of the quality of the sleep or perceived comfort,perhaps based on a duration of uninterrupted sleep). A learningalgorithm determines correction factors to apply to core the calibrationscheme to personalize comfort to baby. This may involve selectingmaterial types that individually captured statistics show result ingreater comfort or sleep for the learned baby, or selecting clothingwith thermal resistance values that are within safe ranges for theambient conditions, but tailored to a specific baby. In one example ababy is perceived to sleep better with slightly lower thermal resistanceclothing choices and so the system suggests recommendations based onthat learning, but still within safe limits. Over time, a newcalibration scheme evolves and improves each time used - baby sleepquality is improved and optimized. With more user input the system couldalso determine sleep clothing type choices, so for example, the baby maytypically sleep better in a particular sleep sack, or not like aparticular sleep sack (i.e., outliers could be detected and notified tothe user). In one example, to effectuate personalized learning, thedevice’s storage medium is adjusted to map the thermal property valuesto different ranges of environmental characteristic values based on anexperienced quality characterization.

Another user interface or display that is not illustrated in FIG. 17 ispersonalized learning of the babies sleep environment itself. Over time,the device may characterize temperature trends (based on stored usagedata) when operated within a given room and may learn patterns whichprovide input to clothing choice recommendations. In one example, thecaregiver selects exactly the right clothing choices for the currentroom temperature, but the input from the room temperature trend patternlearning software suggests that the room will likely heat up throughoutthe duration of sleep-time and so the device suggests a clothing choicewith lower thermal resistance.

Another user interface or display that is not illustrated in FIG. 17 isquantification of time spent in the “thermoneutral” zone. If a caregiveruses the device to perfectly match clothing choices to the ambientconditions, the infant will be in the thermoneutral zone, meaning thebaby expends little or no energy maintaining body temperature, and mostcalories go to growth and development. By constantly comparing the savedcurrent clothing choice with the ambient conditions, a history of thematch can be created which will inform the user of the quality of thebaby’s comfort (i.e, being in the thermoneutral zone) whether awake orasleep. In one example, it may present a chart showing the amount oftime the baby spent within the specified thermoneutral zone, and reporta score indicating how close the sleep-time was to ‘perfect’ (remainingwithin the zone of thermoneutrality for the entire duration of sleep).

Service Based Garment Recommendations

In one example, a garment recommendation device may be embodied as acommunication device with an installed garment recommendationapplication. The device is capable of receiving a user input thatidentifies the temperature for which the baby should be dressed.Alternatively, the device could include a temperature sensor configuredto provide temperature data to the communication device (e.g., athermocouple with a communication adaptor). In this example, many of thefunctions described as being performed by “onboard” components of themeasurement device are performed by an internet-based garmentrecommendation service (e.g., a subscription service).

The garment recommendation device measure (or otherwise determines usingany of the methods described above) an environmental characteristic(e.g., temperature, humidity, and so on (hereinafter “temperature”)) forwhich the baby should be dressed. The temperature is transmitted, viathe internet, to the garment recommendation service. The service wouldaccess a database of recommendations for different temperatures andtransmit a recommendation back to the device for display by the device.The recommendations could be in terms of thermal resistance values thatare suitable for the temperature, a listing of clothing (previouslyrecorded as owned by the user) that would be suitable for thetemperature, material types and/or thicknesses that are suitable forthat temperature, different manufacturers’ listing of garments that aresuitable for that temperature, and so on.

It can be seen from the foregoing description that the describedmethods, circuitries, and devices provide a household suitable handheldand portable measurement device that determines a thermal property ofmaterial and, in some examples, determine and display a suitability ofthe material for the present environment.

Examples can include subject matter such as a method, means forperforming acts or blocks of the method, at least one machine-readablemedium including instructions that, when performed by a machine causethe machine to perform acts of the method or of an apparatus or systemfor measuring a thermal property of a material sample according toembodiments and examples described herein.

Various illustrative logics, logical blocks, modules, and circuitsdescribed in connection with aspects disclosed herein can be implementedor performed with a general purpose processor, a digital signalprocessor (DSP), an application specific integrated circuit (ASIC), afield programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform functions described herein. Ageneral-purpose processor can be a microprocessor, but, in thealternative, processor can be any conventional processor, controller,microcontroller, or state machine. The various illustrative logics,logical blocks, modules, and circuits described in connection withaspects disclosed herein can be implemented or performed with a generalpurpose processor executing instructions stored in computer readablemedium.

While the invention has been illustrated and described with respect toone or more implementations, alterations and/or modifications may bemade to the illustrated examples without departing from the spirit andscope of the appended claims. In particular regard to the variousfunctions performed by the above described components or structures(assemblies, devices, circuits, systems, etc.), the terms (including areference to a “means”) used to describe such components are intended tocorrespond, unless otherwise indicated, to any component or structurewhich performs the specified function of the described component (e.g.,that is functionally equivalent), even though not structurallyequivalent to the disclosed structure which performs the function in theherein illustrated exemplary implementations of the invention. The abovedescription of illustrated embodiments of the subject disclosure is notintended to be exhaustive or to limit the disclosed embodiments to theprecise forms disclosed. While specific embodiments and examples aredescribed herein for illustrative purposes, various modifications arepossible that are considered within the scope of such embodiments andexamples, as those skilled in the relevant art can recognize.

In this regard, while the disclosed subject matter has been described inconnection with various embodiments and corresponding Figures, whereapplicable, it is to be understood that other similar embodiments can beused or modifications and additions can be made to the describedembodiments for performing the same, similar, alternative, or substitutefunction of the disclosed subject matter without deviating therefrom.Therefore, the disclosed subject matter should not be limited to anysingle embodiment described herein, but rather should be construed inbreadth and scope in accordance with the appended claims below.

In particular regard to the various functions performed by the abovedescribed components (assemblies, devices, circuits, systems, etc.), theterms (including a reference to a “means”) used to describe suchcomponents are intended to correspond, unless otherwise indicated, toany component or structure which performs the specified function of thedescribed component (e.g., that is functionally equivalent), even thoughnot structurally equivalent to the disclosed structure which performsthe function in the herein illustrated exemplary implementations of thedisclosure. In addition, while a particular feature may have beendisclosed with respect to only one of several implementations, suchfeature may be combined with one or more other features of the otherimplementations as may be desired and advantageous for any given orparticular application. The use of the phrase “one or more of A, B, orC” is intended to include all combinations of A, B, and C, for exampleA, A and B, A and B and C, B, and so on.

I claim:
 1. A method, comprising: applying non-thermal energy to a firstside of a material sample; sensing, a response of the material sample tothe non-thermal energy; generating non-thermal data indicative of theresponse; and determining a thermal property of the material samplebased on the non-thermal data.
 2. The method of claim 1, furthercomprising: determining an environmental characteristic; determining asuitability of the material sample based on the thermal property and theenvironmental characteristic; and displaying information related to thesuitability.
 3. The method of claim 2 comprising determining theenvironmental characteristic by measuring the characteristic of theenvironment.
 4. The method of claim 2 comprising determining theenvironmental characteristic by receiving data indicative of theenvironmental characteristic.
 5. The method of claim 1, furthercomprising: applying thermal energy to the material sample; sensing atemperature of the material sample; generating thermal data indicativeof the temperature; and determining the thermal property based on thenon-thermal data and the thermal data.
 6. The method of claim 1,comprising: emitting electromagnetic radiation toward the first side ofthe material sample; and measuring an amount of electromagneticradiation on a second side of the material sample; and generating thenon-thermal data indicative of the amount of electromagnetic radiation.7. The method of claim 6, wherein the electromagnetic radiationcomprises non-visible light having a peak wavelength ranging betweenapproximately 750 nm to 1100 nm.
 8. The method of claim 6 comprisingemitting the electromagnetic radiation with varying levels of power. 9.The method of claim 6 comprising: capturing an image of a second side ofthe material sample opposite the first side; and determining the thermalproperty by analyzing the image.
 10. The method of claim 1, comprising:emitting sound toward the first side of the material sample; sensingsound passing through a second side of the material sample opposite thefirst side; and generating the non-thermal data indicative of the sensedsound.
 11. The method of claim 10, comprising emitting sound atapproximately 2 kHz.
 12. The method of claim 1, comprising: contactingthe first side of the material sample with a vibrating source element;sensing a mechanical response of the material sample; and generating thenon-thermal data indicative of the mechanical response.
 13. The methodof claim 12, comprising performing a fast Fourier transform (FFT)analysis on a spectra of the non-thermal data to determine the thermalproperty.
 14. The method of claim 1, comprising determiningcompressibility of the material sample to generate the non-thermal data.15. The method of claim 14, comprising determining compressibility by:contacting the first side of the material sample with a spring-loadedwide-area contact element; measuring a displacement of the spring-loadedwide-area contact element; and generating the non-thermal dataindicative of the displacement.
 16. The method of claim 1, furthercomprising: contacting the first side of the material sample with afirst electrode and a second electrode spaced from the first electrode;measuring a resistance or capacitance of the material sample between thefirst electrode and the second electrode; and determining a suitabilityof the material sample based on the resistance or capacitance.
 17. Themethod of claim 1, further comprising: contacting a surface of thematerial sample with a durometer mechanism comprising a spring having apredetermined spring constant and a probe disposed at a distal end ofthe spring; measuring a compression of the spring; determining durometerdata based on the compression of the spring; determining a surfacesuitability based on the durometer data; and communicating informationrelated to the surface suitability.
 18. The method of claim 1, furthercomprising determining a material identifier characterizing the materialsample based on the non-thermal data.
 19. The method of claim 1, furthercombining the thermal property with a second thermal property determinedfor another material sample.